/*伪类*/
a:link {color:#FF0000;}
a:visited {color:#00FF00;}
a:hover {color:#FF00FF;}
a:active {color:#0000FF;}
/* 伪元素*/
div {
    border-width: 1px;
    border-color: blue;
    border-style:solid;
}

body *{
    border-style: solid;
    border-width: 1px;
    border-color: red;
}

